1. Field of the Invention
This invention relates to electronic circuits, and more particularly, to circuitry for detecting power supply droops.
2. Description of the Related Art
Integrated circuits (ICs) typically receive power from one or more external power supplies. Many modern ICs include multiple power domains, each of which may be powered by a different external power supply with respect to the others. The different power domains may operate at different supply voltages.
During operation, an IC may at time undergo a power supply ‘droop’. A droop may be defined as a temporary drop in the supply voltage for a given power domain. Droops may be caused by one or more of another different factors, such as the simultaneous switching of a number of circuits, temperature variations, process variations, and so forth. Circuitry subject to a power supply droop may experience erroneous operation (e.g., timing failures) as a result thereof. Failures resulting from power supply droop may be considered soft failures, since they are not always repeatable in the absence of the drop in the supply voltage. Accordingly, determining the cause and characterizing such failures may be difficult.